We strongly recommend that you always choose to pay in the local currency when abroad as some merchants will charge you in your base currency and then apply their own foreign exchange fees on top.
The interbank exchange rate is the dynamic rate at which banks swap currencies between one another. It is a real-time rate, which is why it is constantly changing in our app and website. We receive these rates from third parties, such as Morningstar.
If you exchange currencies on weekdays (Mon-Fri UTC) you will receive the interbank exchange rate without any markup or fees - subject to our fair usage terms on all currencies except for Thai Baht, Russian Rubbles, Ukrainian Hryvnia, and Turkish Lira where we add a 1% markup.
On the weekend (Sat-Sun UTC) we fix the rate we provide to protect ourselves against fluctuations, this means we apply markups of:
+0.5% to all major currencies (ie. USD, GBP, EUR, AUD, CAD, NZD, CHF, JPY, SEK, HKD, NOK, SGD, DKK, PLN, and CZK); and +1% to all other currencies including THB, RUB, UAH and TRY. (this means over the weekend THB, RUB, UAH, and TRY have a 2% markup.)
Since the interbank exchange rate is constantly fluctuating, the rate that we lock in for the weekend may not be the same as the rate that is available when the markets open on Monday morning.
As for markup fees, we have a fixed 0,4% markup on any exchange that you make above your plan's free allowance.